Adam Vinatieri’s last-second 48-yard field goal dropped over the crossbar last night and gave the New England Patriots a 20-17 victory over the St. Louis Rams in what may have been the greatest Super Bowl of them all. Under the Superdome’s synthetic sky, 1,500 miles from home, the Patriots shocked the nation and delivered Greater Boston its first professional sports championship since 1986.

On his way to becoming a Bobby Orr/Larry Bird of the new century, Kid Tom Brady produced one final miracle to complete the magic ride of 2001-02. The wonderboy quarterback concluded his stardust season by copping the MVP trophy and becoming the youngest winning QB (24) in Super Bowl history.

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Brady was hardly dominant (16 for 27, 145 yards, one touchdown, no interceptions), but after St. Louis tied the game, 17-17, with 1:30 remaining, he drove the Patriots 53 yards in eight plays (without benefit of timeouts), putting Vinatieri in position to win the game.

So after four quarters of bone-rattling, blood-and-thunder defense, the Patriots won it on a walk-off kick by the kid from South Dakota. And for the second time in three weeks, Patriots long snapper Lonie Paxton celebrated on his back with traditional snow angels amid the confetti of the end zone.

While more confetti fluttered from the ceiling, Patriots owner Bob Kraft accepted the Vince Lombardi Trophy from commissioner Paul Tagliabue and said, ‘’The fans of New England have been waiting 42 years. We are the world champions. At this time in our country, we are all Patriots, and tonight the Patriots are champions.’’

These Patriots seemed to thrive in their position as underdogs. A last-place team one year ago, listed at 75-1 to win the Super Bowl when the season started, they jelled under the leadership of coach Bill Belichick and the quarterbacking of Brady. They won their final nine games, and last night’s shocker ranks as the second-greatest upset in Super Bowl history (the Rams were favored by 14), exceeded only by Joe Namath’s 18-point underdog Jets in 1969.

New England suffocated St. Louis’s high-flying offense, holding the Rams to 3 points over the first three quarters and forcing three turnovers. The fumble and two interceptions led to all of New England’s 17 points up to then. The Rams averaged 31 points in 2001-02 and didn’t score fewer than 15 in any game this year.

’’It was force vs. finesse and something had to give,’’ said Patriot linebacker Tedy Bruschi. ‘’It wasn’t too complicated. We just concentrated on hitting them hard.’’

New England’s ferocious defense hurried and hurt the Rams for 3 1/2 quarters. Warner’s only touchdown pass in the first three quarters was thrown to Patriots cornerback Ty Law.

The second St. Louis turnover came with just under a minute and a half to go in the second quarter. Ricky Proehl caught a pass over the middle and was rocked by Antwan Harris. The ball came loose and was scooped up by New England’s Terrell Buckley, who ran it to the Ram 40.

While the stunned Ram offense tried to regroup, Brady went to work. With 31 seconds left in the half, Brady connected with David Patten on a timing route in the right corner of the end zone. Patten’s circus catch sent the underdogs into the locker room with a 14-3 lead.

The Rams hadn’t trailed by more than 8 points all year. No Super Bowl team had ever overcome a halftime deficit of more than 7 points.

New England’s defense was ever better in the third period, and the Rams were rattled. Patriots cornerback Otis Smith picked off a pass when wideout Torry Holt fell down running a pattern, and that led to a 37-yard field goal by Vinatieri and a 17-3 New England lead.

Then came some anxious moments for Patriot Nation. On a fourth-and-goal from the 3, Warner was hit by Roman Phifer and fumbled. The ball was picked up by Tebucky Jones, who ran the length of the field for a touchdown.

No.

Penalty.

Patriots veteran Willie McGinest was caught holding Marshall Faulk, and the TD came back. Warner eventually scored on a quarterback keeper.

So instead of leading, 24-3, with 10:09 left, the Patriots led, 17-10, with 9:31 left.

Snake-bitten New Englanders fretted. Would McGinest held the tailback succeed Pesky held the ball in our local sports Hall of Pain?

It sure looked that way when the Rams tied the game on a three-play, 55-yard touchdown drive. At best, it appeared Super Bowl XXXVI would be the first to go into overtime.

But Brady had one more miracle in his bag. He took over on his own 17 with 1:21 left and no timeouts. And he did the job. The key play was a 23-yard pass to Troy Brown. A short pass to Jermaine Wiggins put the ball on the 30 and set the stage for Vinatieri.

’’I was just so happy that the guys moved the ball down and gave me an opportunity,’’ said Vinatieri. ‘’Once I kicked it, I knew it was good. I looked up and it was just time to celebrate. It was unbelievable.’’

In the winners’ locker room, a couple of Wheaties boxes surfaced - boxes with the images of Brady and four of his teammates. Brady signed one for Troy Brown, then went back out to the field to do some more interviews.

’’Beat those Red Sox, huh?’’ Kid Brad said with a grin. So there. The drought is over. The Patriots will be defending Super Bowl champs when they first play in brand new CMGI Field next fall. The oft-maligned football team from Foxborough has empowered us with bragging rights across the land.

These Patriots did something no Red Sox team has done in 83 years, something no Bruins team has done in 30 years, and something no Celtic team has achieved since Larry and Friends beat the Rockets in ‘86.

Hold your heads high, New England sports fans. No matter whether you live in Boston, Foxborough, Hartford, or Groton, you woke up this morning in a city of champions. Open the fridge and pull out that bottle of bubbly that’s been chilling for 16 long years.

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